Mounting fixture for tubular lamp sockets



' g- 30,1950 L. G. STAHLHUT 2,951,148

MOUNTING FIXTURE FOR TUBULAR LAMP SOCKETS Filed Jan. 31, 1955 4 Sheets-Sheet l Aug. 30, 1960 G. STAHLHUT 2,951,148

MOUNTING FIXTURE FOR TUBULAR LAMP SOCKETS Filed Jan. 31, 1955 4 Sheets-Sheet 2 Aug. 30, 1960 L. e. STAHLHUT MOUNTING FIXTURE FOR TUBULAR LAMP SOCKETS Filed Jan. 31, 1955 4 Sheets-Sheet 3 Aug. 30, 1960 L. G. STAHLHUT MOUNTING FIXTURE FOR TUBULAR LAMP SOCKETS 4 Sheets-Sheet 4 Filed Jan.

United States Patent O i MOUNTING FIXTURE FOR TUBULAR LAMP SOCKETS Leo G. Stahlhut, Kirkwood, Mo., assignor to Day-Britt:

Lighting, Inc., St. Louis, Mo., a corporation of MIS- souri Filed Jan. 31, 1955, Ser. No. 484,891

Claims. (Cl. 240-5111) This invention relates to improvements in mounting fixtures for tubular lamp sockets, and is particularly applicable to mounting fixtures for use with spring loaded lamp sockets.

Heretofore spring loaded type lamp sockets have not been secured in lighting assemblies so as to assure a rigid or nonyielding support capable of resisting the twisting and turning efiect caused by the continuous load action exerted by the use of spring type sockets. The necessity for providing a nonyielding support has created the objectionable feature that the lamp sockets are very difiicult to remove, and in some cases it requires removal of the whole lighting assembly.

It is an object of the present invention to provide amounting fixture of simple form and construction which will possess accurate locating features and will readily permit assembly and disassambly of the lamp sockets without impairing rigidity of support.

It is also an object of this invention to provide a mounting fixture of the foregoing type having a construction which will assure a rigid mounting of the lamp sockets in a position of accessibility and under conditions of simple tension and compression forces in the structural parts of the fixture.

A further object of this invention is to provide a mounting fixture for lamp sockets of the spring loaded type which may be manufactured to tolerance required for interchangeability of parts.

These and other objects and advantages of the present invention will be set forth in greater detail in connection with the accompanying description of said forms of the invention.

Generally, the invention consists in a mounting fixture formed with an open sided pocket in which two oppositely arranged spaced wall portions of the fixture act to hold the lamp socket in proper position, and wherein one of the spaced walls is formed with recesses for receiving projections carried on the sockets, thereby assuring proper positioning of the sockets. The invention further consists in the foregoing mounting fixture, wherein the 00- operating spaced walls are arranged relative to the main body of the fixture to provide a rigid support for the lamp sockets without interfering with the quick and easy removability of the socket from the open sided pocket.

The invention further consists in the parts and components of the mounting fixture which will be particularly described in view of the embodiments of the invention illustrated in the accompany drawings wherein:

Fig. 1 is a front elevational view of a mounting fixture which embodies the present invention;

Fig. 2 is a side view of the mounting fixture seen along line 2-2 of Fig. 1;

Fig. 3 is an exploded perspective view of the mounting fixture and typical spring loaded type tubular lamp sockets adapted to be removably supported in the mounting fixture;

2,951,148 Patented Aug. 30, 1960 Fig. 4 is a front elevational view of a mounting fixture of modified form;

Fig. 5 is a transverse sectional elevational view taken along the line 5-5 in Fig. 4;

Fig. 6 is an exploded perspective view of the mounting fixture shown in Fig. 4, and typical spring loaded type tubular wall sockets adapted to be removably mounted therein;

Fig. 7 is a front elevational view of a further modified mounting fixture.

Fig. 8 is a transverse sectional elevational view as seen along the line 8-8 in Fig. 7;

Fig. 9 is a perspective view of the mounting fixture shown in Fig. 7, together with typical tubular lamp sockets removably positioned in the mounting fixture;

Fig. 10 is a longitudinal sectional elevational view of a lighting fixture assembly in which the mounting fixture of Fig. 9 is incorporated; and

Fig. 11 is an end elevational view of the assembly of Fig. 10, part of the same being shown in sectional detail.

Reference will now be directed to Figs. 1, 2 and 3, wherein one form of the present mounting fixture is shown. The fixture generally indicated at 10 includes a sheet metal body having a main wall 11 which connects walls 12 and 13. The wall 13 is provided with spaced wall portions 14 which are integrally connected thereto at the bent or closed corners 15. Each of the wall portions 14 has one of its edge margins 16 (Fig. 2) lying adjacent the edge 17 of the main wall 11. The wall 12 is provided with oppositely positioned wall portions 18 which are spaced outwardly from the wall portions 14 and are also offset relative to the walls 14 as will be more particularly described. Each of the wall portions 18 constitutes a part of the wall 12 by being connected thereto through an angle wall having the angularly related portions 19 and 2t which mutually act to stiffen and brace wall portion 18. Wall 19 is free of connection with the main wall 11 so that wall portion 18 is free to pivot about the closed corner 21, thereby permitting a change in spacing between the wall portions 18 and 14.

The wall portions 14 and 18, and the wall 20 form three sides of a pocket which is open at the bottom and at the two opposite ends. This may be seen by comparing Figs. 1 and 2. Additionally, wall portion 18 is provided with a notch defined by the edges 18a and 18b. The notch edge 18a is, in this instance, arranged to be opposite and slightly onut of alignment with the spaced edge 14a of wall portion 14, as may be seen in Fig. 2. Wall portion 14 is provided with an aperture 22 which is spaced from but in axial alignment with an aperture 23 in wall portion 18. In addition, wall portion 14 is formed with an aperture 24 adjacent to the corner 15, and generally opposite the notch 18, particularly the notch edge 18b.

The mounting fixture 10 is suitably secured in a horizontally arranged lighting fixture (see Fig. 10) in the position of Fig. 1, whereby the pockets on each side of the body are. open downwardly and longitudinally. Attachment of the fixture is through the wall 12 or the wall 11, suitable openings 25 and 26 in wall 11 being provided for the purpose of access for electrical wires. The whole body 10 is stiffened by means of a plurality of corner indentations 27 made in the forming process.

Referring to Fig. 3, a typical spring loaded lamp socket is shown at 30. A socket of this general character is disclosed and claimed in Kukla Patent 2,495,196, dated January 17, 1950. This socket is seen to include a base 31, a projecting housing 32 and a lamp contact plug 33 which is movable through an aperture 34 in the housing 32. A suitable spring 38is contained in the housing 32 in position to abut the inner end of plug 33 for the purpose of maintaining the plug in" extended position. The base 31-ofsocket-30 is formed with projecting pins, lugs, or the like 35 and 36 whichare adapted to be utilized in the location and retention of the socket in the body 10 of themountingfixture:

Assembly of the socket 30 in the'open sided pocket'of' body 10 'is accomplished positioningnthe base 31' in the notch formed in wall portion 1.8 while maintaining: the position of the socket. 30r'as shown'intFig. 3-. The socket 30 is them-pushed'between the wall portions .14 and lbbyreason of the fact thatthese wall portions are capable of relative separation to receive the end 3111 of thesock-et'base 315. Continued 'nrovementin this direction will bring pin 36 on base 31 adjacent opening. 24, and pin 35 wilIassumei-ai positiorr=adjacent edge 14a and against the outer surface of wall-portion 14. The forward movement of so'cket'30a-will be-arrestedby contact between the face; of housing: 32 and the margin 18b" of notch 18. At this time, the socket 301C311 be'pushed toward the wall 2010: bring the housing; 32 into contact with notch margin 18a; Thisla-ttermovement will result in locating pin 35 snapping over the edge 1=4a"of wall portion 14- and lOCQfiIlgwPiHQFSHhPPlIlg? intothe opening 24. The snap action is= attained. because of the resiliency and relative movement provided between wall portions 14 and 18. Once-the socketv 30- hasbeenfully. positioned, as determined-by the locating'pins 36 and 35 and the margins of notch 18, a suitable securing means is inserted in the aligned apertures 22 and23 to retain or clamp the wall portions 14 and 18 against the opposite faces of the socket base 31. The retainingmeans is shown in Fig. l at 37.

In Fig. 3, the socket 30 isshown provided with theinternal spring 38 which asserts an outward thrust on the plugi33 at all times. This spring 38 is intended to push the plug 3-3 against the end contact (not shown) of a tubular type lamp, whereby positive electrical contact may be made for the purpose of preventing electrical arcing, poor contact due to atmospheric conditions, and to overcome vibration or similar relative movement between the contact in the plug and the tubular lamp. The constant pressure of spring 38on'the tubular lamp creates a force along the length of the lamp which is received by the socket 30 and by a co operatingsocket (as shown in Fig. at the opposite'end. Therefore, there is a constant force directed along the axis of the plug-33 which, in. turn, means that a turning moment is'exerted through the socket'housing- 32 upon the base 31, and this is transmitted into the body of the mounting fixture 10. According to the right hand portion of the view of Fig. 3, this turning moment assumes -a counterclockwise direction about edge 17 of body wall 11. The effect of thisforce is experienced also about the rearward margin 16' of wall portion 14. The accompanying reaction in wall portion 18 exerts tension in the wall 12 of body 10. The wall portion 18 is directly connected through the means 37 with Wall portion 14, whereby the counterclockwise moment on wall portion 14 is resisted by the action of wall portion 18, and wall portion 18 is maintained in rigid relationship through the rigidity of theangularly related legs 19 and 20 and by the strength in tension of the body wall 12. Accordingly, a rigid mounting is achieved'for the socket 30, and'proper posi-. tioning of the socket is obtained by means of the locating opening 24 in wall portion 14, in co-operation with the margins of the n'otch'in wall portion '18.

The foregoingdescription has been given with respect to one of the pockets-(the right hand one in particular) of the mounting fixture body 10. It is obvious that the opposite pocket is similarly but reversely formed. Therefore, the foregoingdescription and" reference numerals will applyequally to either of the pockets.

In Figs. 4, Sand 6 amodifiedfform of mounting fixture is shown at 40. body havingamainwall 41 which connects walls 42 and This mounting; fixture 40'includes a 44. The opposite margins of wall 42 are slightly convergent-ly directed toward-the wall 41- (Fig. 4) and awall portion 43 is carried by the wall 42 at each of these tapered margins. The wall portions 43 each extend toward the wall 44 of the body, but each is free of contact with the wall 44 and with the wall 41. The opposite margins of walk-44 are similarly angularly directed to form integral wall. portions. 45.. In Fig- 6, the wall portiohs43and45-"are shown inspaced relationship at each end of the b'od'y'4il so that a pocket is formed between each of thespacedpairs-of wall portions '43 and 45. This pocket issimilar: to'the pocket formed between wall portions 14 and 18 in the form of the body shown at 10 in Fig.1. Wall. 43 is permitted a certain degree of movementrelative to wall 42 by being free of contact along its remaining three margins; and wall portion 45 is free to move about the corner 46 and relative to wall 44 since its other three margins are free. One margin of wallportion 45 isprovided with an'inturned stifiening flange 47 which isslidable against'the-surface of wall 41; The opposite margin of wallportion 45 is formed with an angularly formed attachment tabv 51.v

As described above,,=the spaced wall-portions 43 and 45 form a pocket therebetween to receive the base 31 of the tubular lamp socket 30. The wall portion 45 is. formed with a notch" having. margins 45a, 45b and 45c. Margins 45a and'4'5jc are spaced apart a distance equal to' the width'of'the socket housing 32 and margin 45bforms'the closed" end'of' the'notch for the purpose of locating thefron't face 34 ofth'e sock'ethousing in the body 40. Wall portion 4?; is provided with a pair of openings or notches 48 adaptedjto receive the pins 35 and 36formed'on the base'3'1of socket 30; In addition,-

aligned apertures 49'and 50" are formed in the respective wall portionsi43 and'45 so that. the securing means 37 (Fig; 1) may beinserted to clamp the wall portions 43and 45 against the oppositesidesof the socket base 31.

The 'projectingplug'33 in theisocket 30 is continuously subjected to pressure from the internal spring 38, whereby a counter clockwiseturning. moment (right hand portion of Fig. 6) isexerted at the closed corner 43a between wa-lls4 3r' a'nd42, and'the accompanying reaction in wall portion 45 is resisted by tension in the wall 44 of the body '40: Additional strength in wall '44 is obtained by meansof' the-marginal flange 44a.

A-modified mounti-ng fixtureis disclosed in Figs. 7, 8 and 9. This form of the mounting'fixture comprises a body 52 having-' -a-mai n* wall 53which' connects wall portions54 and 55; The body also includes a wall extension 56 carried by the wallportion'55. The body 52 is provided with a side wall 57 which is integral with the wall 53 and wall-extension 56- for the purpose of stiffening thebody. Wall extension'56 is formed with one or more notchesor elongated'openings 58 (two being shown) for the purpose oflocating-the socket housing 32 in position allowing the plug 3-3" to project outwardly for engagement'with the. endportion ofthe tubular lamp (not shown). 1

As shown. in Figs; 7 andf9; each of-the wall portions 54 is provided witlr spaced openings 59 which are adapted to receivethe locating-pins 35 and 360m the socket-base-Sl for locating the socket-30 in proper position, assisted by the opening 58 in-wallextension 56 of the body 52. Pins 35 and 36 are snap fitted into the openings 59 by reason of the relative yieldability of wall portion .54 with respect to the spaced wall portion 55. It is 'observ'edthat wall portions 54 and 55 define a pocket in the body 52 to receive the'socket 30. Suitable apertures 60 and 61 in alignedrelation are formed respectively in wall portions 54 and 55 to receive the securing means 37, whereby the's-ocket' base 31 may be secured in the pocket.

Figs. wand-'11 disclosea lighting fixtureof a form which includes: a troffcr structureGS' and a headstructure 66 of-any 'welllmown" form. The lightingfixture is equipped with a longitudinally spaced pair of tubularlamp socket mounting fixtures of the type shown at 52 in Figs. 7, 8 and 9. For example, the left hand one of the mounting fixture bodies 52 is provided with a spring loaded plug type socket 30 and the right hand one of the bodies 52 is provided with a complementary socket 30a which difiers from the socket 30 in that no spring mounted plug is provided. Instead the socket 300 is equipped with a suitable fixed internal contact indicated at 3%. The mounting fixtures 52 are secured in the lighting xture head 66 in opposed relationship so that the sockets 3i) and 39a are in alignment to receive the tu ular lamp 67. The lamp is normally placed in the lighting fixture by engaging one end with the springloaded plug 33 and depressing the same sufficiently to perrrfit the opposite end of the lamp 67 to be positioned with its end engaged with the internal contact 3012 in socket 30a. This installation of the lamp 67 requires a certain degree of over travel of the plug 33 so that when the lamp is in proper position, the plug 33 will remain slightly inwardly displaced, thereby assuring positive loading by the internal spring 38.

The foregoing described embodiments of the present invention include the advantages of simplicity of construction, positive securing of the lamp sockets, and spaced arrangement of spaced socket receiving pockets wherein the pockets are fixed by intervening walls of the mounting body against displacement due to the constant spring load from the socket springs pushing on the lamps. The intervening walls of the mounting body serve in either tension or compression for the most part, assisted by the clamping effect of the removable securing means,

What i claim is:

1. In a mounting fixture for supporting a lamp socket in a positive but releasable manner, the combination with the lamp socket of a mounting fixture comprising a body having a main space defined by angularly related walls and an adjacent pocket space to receive the lamp socket, said pocket space being defined by first and second walls spaced apart and other wall means connecting said first and second walls in relatively yieldable relation to permit said pocket space to be increased to receive the lamp socket, said first wall having an enlarged socket locating opening therein and said second wall having at least one aperture smaller than and disposed opposite said locating opening, said opening and aperture being engaged by difierent parts of the lamp socket to position the same and the yieldable relation of said first and second walls causing the latter walls to retain the lamp socket at opposite sides in a push-fit relation, and means releasibly engaging said first and second Walls to secure the same against yielding movement.

2. The mounting fixture set forth in claim 1 wherein said first and second walls are parallel and said other wall is integral with said first and second walls and angulsrly connected therewith to define a third wall of the pocket space.

3. The mounting fixture set forth in claim 1 wherein the enlarged locating opening in said first wall has at least two angularly related adjacent edges engaged by the lamp socket, and said aperture in said second wall being substantially aligned with one of said angularly related edges of said locating opening.

4. The mounting fixture set forth in claim 1 wherein the enlarged locating opening in said first wall has spaced apart edges engaged by the lamp socket, said aperture in said second wall being substantially aligned with one of said spaced apart edges of said first Wall, and said second wall. having other lamp socket alignment means substantially aligned with the another of said spaced apart edges of said first wall.

5. In a mounting fixture for supporting a lamp socket in a positive but releasable manner, the combination with the lamp socket of a mounting fixture comprising, an integral body formed with angularly related main walls and having a lamp socket mounting space adjacent the main walls, said mounting space being defined by 'a first wall integrally connected to one of said main walls and being angularly related and yieldable with respect thereto and a second wall spaced from said first wall and being integrally connected to another one of said main walls in angular relation with respect thereto, said first and second Wall being substantially parallel and having openings therein to engage and position the lamp socket .therebetween, said first wall yielding relative to said second Wall to admit the lamp socket fully into the mounting space and retain the same in position between said first and second walls and engaged in said openings.

References Cited in the file of this patent UNITED STATES PATENTS 1,726,884 Brown Sept. 3, 1929 1,979,568 OConnor et a1. Nov. 6, 1934 2,250,276 Rutherford July 22, 1941 2,314,038 Elting Mar. 16, 1943 2,345,234 Carter Mar. 28, 1944 2,366,816 Stapleton Jan. 9, 1945 2,520,593 Chatfield Aug. 29, 1950 2,595,487 Runge et al. May 6, 1952 2,667,570 Goldthorpe Jan. 26, 1954 2,753,444 ZUI'SJWSkl July 3, 1956 2,820,241 Schlage Ian. 21, 1958 

